Dynamically associated neighbor awareness networking (NAN) discovery windows for fine timing measurement

ABSTRACT

Certain embodiments herein relate to a dynamic pre-association between Neighbor Awareness Networking (NAN) discovery windows and fine timing measurement (FTM) communications. A wireless station may trigger an FTM procedure during a NAN discovery window by the transmission of a NAN Service Discovery Frame (SDF). In addition to the FTM communications, an indication of a discovery window for which a subsequent FTM communication is expected to occur is also transmitted. In some embodiments, an FTM range report may also be transmitted with the indication.

PRIORITY CLAIM

This application claims priority to U.S. patent application Ser. No.14/546,045, filed on Nov. 18, 2014, entitled “Dynamically AssociatedNeighbor Awareness Networking (NAN) Discovery Windows for Fine Timing”which claims priority to U.S. Provisional Patent Application No.62/010,667, filed on Jun. 11, 2014, entitled “Adaptive Discovery Windowfor Fine Timing Measurement” the disclosures of which are herebyincorporated by reference in their entirety.

BACKGROUND

Wireless devices (also referred to as “wireless stations”) areincreasingly dependent upon their proximity to other wireless devices ascontext for various applications. In some approaches, an initiatingwireless station (e.g., a smartphone or other mobile wireless device)can determine its relative location by communicating with respondingwireless stations (e.g., a printer or other stationary wireless device).Such approaches can involve analyzing communications between theinitiating wireless station and the responding wireless station to helpdetermine the initiating wireless station's proximity (e.g., rangemeasurement) to the responding wireless stations. In some instances, theproximity determinations may not be responsive enough to provideadequate performance for the various applications that rely on thedeterminations between stations. For example, a user may perceive that awireless device or program executing thereon is slow to respond,inaccurate, or unusable if the wireless device is unable to receivetimely proximity determinations based on the communication betweenstations.

BRIEF DESCRIPTION OF THE FIGURES

The detailed description is set forth with reference to the accompanyingfigures. In the figures, the left-most digit(s) of a reference numberidentifies the figure in which the reference number first appears. Theuse of the same reference numbers in different figures indicates similaror identical items.

FIG. 1 a schematic diagram depicting an embodiment of a NeighborAwareness Networking (NAN) cluster;

FIG. 2 is a schematic diagram depicting an embodiment for a fine timingmeasurement (FTM) determination of the distance between an initiatingwireless station and a responding wireless station;

FIG. 3 is a schematic diagram depicting a dynamic pre-associationbetween NAN discovery windows and FTM communications according to anexample embodiment of the present disclosure;

FIG. 4 further depicts the schematic diagram of FIG. 3 illustrating atransmission of an FTM range report according to an example embodimentof the present disclosure;

FIGS. 5-7 are schematic diagrams depicting different dynamicpre-associations between Neighbor Awareness Networking (NAN) discoverywindows and FTM communications according to example embodiments of thepresent disclosure;

FIG. 8 is a block diagram illustrating a process for a dynamicpre-association between Neighbor Awareness Networking (NAN) discoverywindows and FTM communications according to example embodiments of thepresent disclosure; and

FIG. 9 depicts a block diagram of an example embodiment of a wirelessstation according to example embodiments of the present disclosure.

Certain implementations will now be described more fully below withreference to the accompanying drawings, in which various implementationsand/or aspects are shown. However, various aspects may be implemented inmany different forms and should not be construed as limited to theimplementations set forth herein; rather, these implementations areprovided so that this disclosure will be thorough and complete, and willfully convey the scope of the disclosure to those skilled in the art.Like numbers refer to like elements throughout.

DETAILED DESCRIPTION

Embodiments herein relate to, among other things, dynamicpre-association between Neighbor Awareness Networking (NAN) discoverywindows and Fine-Timing-Measurements (FTM) communications in a NANcluster. In some embodiments, a wireless station may trigger an FTMprocedure by transmitting a NAN Service Discovery Frame (SDF) during aNAN discovery window. In some embodiments, the NAN discoverycommunications and FTM communications may occur on different channels.In addition to the FTM communication, the wireless station may send anindication of an expected discovery window for a subsequent FTMcommunication. A receiving wireless station may then receive theindication of the discovery window and send or receive a subsequent FTMcommunication in the indicated discovery window. In this manner, awireless station may dynamically configure the rate of FTM rangemeasurements triggered within periodic NAN discovery windows. In someembodiments, after an FTM range measurement is determined, an initiatingwireless station may also send an FTM range report with the indicationof a discovery window.

FIG. 1 depicts an example Neighbor Awareness Networking (NAN)environment 100 in which the dynamic pre-association between NANdiscovery windows and FTM communications described herein may beimplemented. The NAN environment 100 may include wireless stations 102that may wirelessly communicate over a wireless network using a wirelesscommunication protocol. In some embodiments, the wireless stations mayinclude mobile wireless stations, such as a tablet computer 102A, asmartphone 102B, and a wearable computer 102C (e.g., a smartwatch, anoptical head-mounted display, and the like). In some embodiments, thewireless stations 102 may include relatively stationary wirelessstations 102D and 102E. For example, stationary wireless stations 102Dand 102E may include devices such as printers, appliances (e.g.,refrigerators, microwaves, stoves, etc.), audio and video devices (e.g.,televisions, monitors, video cameras, stereo receivers, set top boxes,thermostats etc.), residential controls (e.g., garage door openers,light switches, door locks etc.), and other suitable devices.

The example environment 100 can include an indoor facility, such as anairport terminal, office, a residence, a shopping mall, a universitybuilding, or other interior space that may include walls (not shown) andother items located within the interior space and the one or morewireless stations may be within the indoor facility. In additional oralternative embodiments, the example environment 100 can include one ormore buildings and the one or more wireless stations 102 may be insideor outside of the buildings in any desirable configuration.

In some embodiments, the wireless stations may belong to a NAN cluster104. The wireless stations 102 may be configured to communicate over awireless network according to one or more wireless communicationprotocols. In this context, a protocol refers to parameters used tocommunicate, such as a channel on which communications occur, timing ofcommunications (e.g., timing of discovery intervals), etc. In anotherexample, the wireless stations 102 of the environment 100 may alsocommunicate data, such as data associated with a particular applicationthat is common to each wireless station 102. It should be appreciatedthat, in the contexts described further below describing communicationbetween two wireless stations, any one of the wireless stations 102 maybe an initiating wireless station and any other of the wireless stations102 may be a responding wireless station. For example, the tabletcomputer 102A may be an initiating wireless station and the stationarywireless station 102D may be a responding wireless station. Similarly,in another example, the stationary wireless station 102E may be aninitiating wireless station and the wearable computer 102C may be aresponding wireless station.

In the environment depicted in FIG. 1, a wireless station 102 may sendvarious NAN discovery communications during a time interval (referred toas a “discovery window”) associated with advertisement of the wirelessstations 102. The discovery communications indicate a post-discoverycommunication technique or protocol for communicating within theenvironment 100 during or after the discovery window.

In some embodiments, a Post NAN discovery communication technique mayinclude techniques for determining the distance between an initiatingwireless station and a responding wireless station. For example, aninitiating wireless station can communicate with a responding wirelessstation to determine a respective distance from the responding wirelessstation. In some embodiments, the initiating wireless stations canmeasure their respective distances from initiating wireless stationsbased at least in part on the time-of-flight of one or more timingmessages transmitted to the initiating wireless stations by theresponding wireless stations and/or one or more messages transmitted bythe initiating wireless station to the responding wireless station. Atiming message transmitted from a responding wireless station to aninitiating wireless station can include an instruction to the initiatingwireless station to record the time the initiating wireless stationreceives the timing message and a time that a previous message,transmitted by the initiating wireless station, was received by theresponding wireless station. A timing message transmitted from aresponding wireless station to an initiating wireless station caninclude an instruction to the initiating wireless station to record thetime the initiating wireless station receives the timing message; a timethat a previous message, transmitted by the responding wireless station,was received at the initiating wireless station. For clarity, a timingmessage comprising an acknowledgement is referred to as anacknowledgement message. As described below, an initiating wirelessstation can determine the time-of-flight of timing messages based atleast in part on the contents of the timing messages.

As used herein, the time-of-flight of a timing message refers to theapproximate difference between the time a timing message is sent by aresponding wireless or an initiating wireless station and the time thetiming message is received by the respective initiating wireless stationand the responding wireless station 102. In some embodiments, aninitiating wireless station can determine its distance from a respondingwireless station 102 using FTM techniques (also referred to as a “FineTiming Measurement procedure”). In some such embodiments, as explainedbelow, one or more timing messages are exchanged between the initiatingwireless station and the responding wireless station and an initiatingwireless station can determine the time-of-flight of at least one of thetiming messages, as described below. Based at least in part on thetime-of-flight of the one or more timing messages, the initiatingwireless station can determine its distance from the responding wirelessstation. The initiating wireless stations can transmit and receivemessages from the responding wireless stations using a WiFi signal, aWiFi Direct signal, or via various other wireless communicationsprotocols. In some embodiments, the NAN protocol may be operative toperform service discovery, where a following FTM procedure can be usedto determine distance between wireless stations, for example.

FIG. 2 is a simplified schematic 200 of an example embodiment fordetermining the distance between an initiating wireless station 202 anda responding wireless station 204. In FIG. 2, “t” denotes time.Initially, the initiating wireless station 202 sends an FTM Request(“FTM Req”) 206 to the responding wireless station and, in response, theresponding wireless station 204 sends an acknowledgement of the request(“ACK_(R)”) 208 to the initiating wireless station 202. At time t₁, theresponding wireless station 204 sends a timing message, FTM₁, to theinitiating wireless station 202 and the responding wireless station 202stores the time FTM₁ was sent (t₁). At time t₂, the initiating wirelessstation 202 receives FTM₁ and records the time it was received (t₂). Attime t₃, the initiating wireless station 202 transmits anacknowledgement message 212 (ACK₁) to the responding wireless station204 and records the time it sent ACK₁ (t₃).

In some embodiments, ACK₁ can include an indication to the respondingwireless station 204 that FTM₁ was received by the initiating wirelessstation 202. At time t₄, the responding wireless station 204 receivesACK₁ and, responsive to receiving ACK₁, records the time it was received(t₄). At time t₅, the responding wireless station 204 transmits a timingmessage 214 (FTM₂), including the recorded times t₁ and t₄ to theinitiating wireless station 202, which is received at time t₆. Afterreceiving FTA₂ the wireless station 202 may send an acknowledgment 216(ACK₂). The initiating wireless station 202 can then determine thedistance to the responding wireless station 204 using the times t₁-t₄,wherein the time-of-flight of FTM₁ can be taken as t₂-t₁ and thetime-of-flight of ACK₁ can be taken as t₃-t₄. In one example embodiment,the distance R between the responding wireless station 202 and 204, canbe given by Equation 1:

$\begin{matrix}{R = {c\frac{\left( {t_{4} - t_{1}} \right) - \left( {t_{3} - t_{2}} \right)}{2}}} & (1)\end{matrix}$

where c is the speed of light (about 3×10⁸ m/s). The distancedetermination may be referred to herein as an “FTM range measurement.”While, for clarity, FTM and ACK are used herein to refer totransmissions by the responding wireless stations 202 and transmissionsby the initiating wireless stations 204, respectively, a person ofordinary skill in the art will understand that both transmissions can betiming messages and the content of the transmissions FTM and ACK can bethe same, similar or different.

As mentioned above, the FTM communication is a single burst during theNAN discovery window described above. The NAN discovery window sets themeeting time for two wireless stations such that the FTM procedure istriggered within the NAN discovery window. Thus, the rate of determinedrange measurement rates may be limited by the ability to trigger an FTMprocedure during the NAN discovery windows specified by a version of theNAN protocol. A version of the NAN protocol may define a fixedperiodical relationship between the NAN discovery windows and triggeredFTM procedures, such that FTM range determinations may only be triggeredbased on a fixed rate of specific NAN discovery windows. In suchinstances, the rate and accuracy of FTM range determinations (resultingfrom FTM range procedures triggered within NAN discovery windows) mayaffect the performance of applications executing on a wireless station.For example, an application may expect a relatively high rate of rangedeterminations to meet a specific level of responsiveness andperformance. Additionally, a mobile wireless station moving at orgreater than a minimum speed toward another wireless station may desirea higher rate of range determinations for improve range accuracy.

Embodiments of the techniques described herein include a dynamicpre-association between FTM procedures and NAN discovery windows. Insome embodiments, the dynamic pre-association techniques describedherein may be implemented in a version of the NAN protocol. As describedfurther below, a discovery window indication may be sent during the FTMprocedure to indicate an expected discovery window for a subsequent FTMprocedure. Another wireless station may respond in the indicateddiscovery window to enable the wireless stations to obtain FTM rangemeasurements at a desired time and, in some embodiments, at a desiredrate. Consequently, the wireless stations may coordinate pre-associationto provide improved responsiveness for the on-going FTM rangemeasurements. Additionally, as described further below, the dynamicpre-association between the FTM procedure and the NAN discovery windowsmay be configured to optimize the responsiveness (e.g., the rangemeasurement rate) vs. power consumption.

FIG. 3 is a schematic diagram illustrating dynamic pre-associationbetween NAN discovery communications 300 and FTM communications 302 inaccordance with the techniques described herein. As shown in FIG. 3, insome embodiments, the NAN discovery communications may be transmitted ona first channel 304 and the FTM communications may be transmitted on asecond channel 306. In other embodiments, the NAN discoverycommunications and FTM communications may be transmitted on the samechannel.

As shown in FIG. 3, a NAN discovery interval 308 is depicted thatincludes the start of a first NAN discovery window 310 and correspondsto the time interval between NAN discovery windows. In the first NANdiscovery window 310, NAN synchronization beacons 312 may be transmittedto assist wireless stations within a NAN cluster synchronize theirclocks. In some embodiments, a wireless station in a NAN cluster maytransmit at least one synchronization beacon during a discovery windowsuch as the first discovery window 310. During the NAN discoveryinterval 308, discovery beacons 314 may also be transmitted by wirelessstations within a NAN cluster. The discovery beacons 314 may assistother NAN-capable wireless stations discover the NAN cluster.

FIG. 3 also depicts a second NAN discovery window 316 that occurs afterelapse of the discovery interval 308. Following the initial NANdiscovery, a wireless station may transmit a NAN Service Discovery Frame(SDF) 318 during the NAN discovery window 314 to trigger an FTMprocedure with another wireless station. The NAN SDF 318 may includeinformation regarding the FTM procedure such as, for example, a channelfor the FTM communications, and a time and/or duration of window for thecommunications. In some embodiments, if a wireless station wants tolimit the set of target stations for FTM, it can publish a set of targetNAN stations for FTM.

As shown in FIG. 3 and as mentioned above, the FTM procedure may beperformed on a second channel 306. An FTM communication 320 (e.g., atiming message), in accordance with the procedure described above andillustrated in FIG. 2, may be sent after the FTM procedure is triggeredfrom within the discovery window 306. In addition, an indication 322 ofthe discovery window for the next expected FTM communication is sent.The discovery window indication 322 may include any suitable indicationthat enables a wireless station to determine the occurrence of adiscovery window. In some embodiments, the discovery window indication322 may include a time interval, a specific time, pointer to a SDF, orany suitable indication or combination thereof.

The indication 318 indicates to other wireless stations the nextdiscovery window a subsequent FTM communication is expected. Forexample, an initiating wireless station may desire a relatively highrate of range measurements to ensure adequate responsiveness of anapplication. In such instances, after an FTM procedure, the initiatingwireless station may send an indication of the discovery window forwhich it desires a subsequent FTM procedure. In some embodiments, thereceiving wireless station may respond according to this expectation.Additionally, or alternatively, the receiving wireless station may alsosend its own discovery window indication for which it expects asubsequent FTM procedure. In this manner, each station may negotiate fora desired discovery window for the next expected FTM communications.

As shown in FIG. 3, the indicator 322 may indicate a discovery window324 that occurs immediately after the previous discovery window 316. Thediscovery windows 316 and 324 may be separated by a second discoverywindow interval (not shown). During this next discovery window 324, awireless station may transmit a NAN SDF 326 to trigger a subsequent FTMprocedure, thus enabling the wireless station to obtain another FTMrange measurement without waiting for a later discovery window. Thus, asshown in FIG. 3, another FTM communication 328 (e.g., a timing message)and another discovery window indication 330 may be transmitted on thesecond channel 306 after triggering of another FTM procedure. In thismanner, another FTM procedure may be performed and another discoverywindow may be negotiated for the next FTM communication.

In some embodiments, the range measurement report determined from an FTMprocedure may also be provided with the discovery window indication.FIG. 4 depicts the simplified schematic of FIG. 3 and illustrates theaddition of the FTM range measurement report to the discovery windowindication.

As shown in FIG. 4 and as described above, after the second discoverywindow 316, the FTM communication 328 and an indication 330 of adiscovery window is sent. In addition, an FTM range report 332 may besent with the indication 330. The FTM range report may include an FTMrange determination based on the previous FTM communications. Aresponding wireless station that desires an FTM range determination canobtain the range determination from the FTM range report transmittedwith the discovery window indication 330. Advantageously, the respondingwireless station does not need to initiate an FTM procedure to obtain aFTM range measurement and avoid an additional delay (e.g., anotherdiscovery window cycle) to obtain an FTM range measurement.

In some embodiments, the pre-association between the FTM procedure andthe NAN discovery windows may be dynamically configured to meet desiredpower consumption and responsiveness. For example, a wireless stationgreater than a distance threshold away from another wireless station maychoose a less responsive range measurement (e.g., a lower rate of FTMprocedures) to decrease power consumption. After the wireless station iswithin a distance threshold, the wireless station may desire a moreresponsive range measurement (e.g., a higher rate of FTM procedures) atthe cost of increased power consumption.

FIGS. 5-7 are three schematic diagrams illustrating different dynamicpre-associations between NAN discovery windows and FTM communications inaccordance with the techniques described herein. As described below,FIGS. 5-7 depict pre-associations in order of decreasing rangemeasurement rates and power consumption. Similar to the figuresdescribed above, FIG. 5 depicts NAN discovery communications 500 on afirst channel 504 and FTM communications 506 on a second channel 508 inaccordance with the techniques described herein. The NAN discoverycommunications 500 include discovery windows 508, 510, 512, and 514,which may occur according to a fixed period and may be separated bydiscovery window intervals (not shown).

As shown in FIG. 5, a NAN SDF 518 may be sent during the first discoverywindow 510 to trigger an FTM procedure on the second channel 506,resulting in an FTM communication 520. In accordance with the techniquesdescribed above, an indication 522 of a discovery window for an expectedsubsequent FTM communication is also sent. In the embodiment depicted inFIG. 5, the next available discovery window 510 is indicated. Forexample, a NAN SDF 524 may be sent during the discovery window 510 totrigger a subsequent FTM procedure. Here again, an FTM communication 526and an indication 528 of a discovery window may be sent. To maintain ahigher rate of range measurements, the indication 528 may indicate thenext available discovery window 512. As also illustrated in FIG. 5,another NAN SDF 530 may be sent during the indicated discovery window512 to trigger yet another FTM procedure. The next FTM communication 532and discovery window indication 534 sent are also shown in FIG. 5.Accordingly, in the embodiment depicted in FIG. 5, the wireless stationsending the communication may desire more frequent FTM procedures andthus a higher rate of FTM range determinations to ensure a level ofresponsiveness for an application. However, as will be appreciated, morefrequent FTM communications may result in increased power consumption,such as compared to the pre-associations depicted in FIGS. 6 and 7.

FIG. 6 depicts another dynamic pre-association between NAN discoverycommunications 600 on a first channel 604 and FTM communications 606 ona second channel 608 having a lower rate of range measurements anddecreased power consumption as compared to the pre-association depictedin FIG. 5. As shown in FIG. 6, the NAN discovery communications 600include discovery windows 608, 610, 612, and 614, which may occuraccording to a fixed period and may be separated by discovery windowintervals (not shown).

As depicted in FIG. 6, a NAN SDF 618 may be sent during the firstdiscovery window 610 to trigger an FTM procedure on the second channel606. According to the techniques described above, an FTM communication620 and an indication 622 of a discovery window 612 for an expectedsubsequent FTM communication is also sent. In the embodiment depicted inFIG. 6, the third discovery window 612 is indicated as opposed to thenext available discovery window 610. Thus, by indicating a laterdiscovery window 612 instead of discovery window 610, the wirelessstation may not desire an FTM range determination until occurrence ofthe later discovery window 612. In such an embodiment, although updatesto the FTM range determinations may occur at a lower rate than thoseoccurring in FIG. 5, the power consumption by the wireless station maybe decreased due to the less frequent FTM communications.

FIG. 7 another dynamic pre-association between NAN discoverycommunications 700 on a first channel 704 and FTM communications 702 ona second channel 706 having a lower rate of range measurements anddecreased power consumption as compared to the pre-association depictedin FIG. 6. As shown in FIG. 7, the NAN discovery communications 700include discovery windows 708, 710, 712, and 714, which may occuraccording to a fixed period and may be separated by a discovery windowinterval (not shown).

As shown in FIG. 7 and similar to the embodiments described above, a NANSDF 718 may be sent in the first discovery window 710 to trigger an FTMprocedure on the second channel 708. In accordance with the techniquesdescribed above, an FTM communication 720 and an indication 722 of thenext discovery window for an expected subsequent FTM communication isalso sent. In the embodiment depicted in FIG. 7, the fourth discoverywindow 714 depicted in FIG. 7 is indicated, as opposed to earlieroccurring discovery windows 710 and 712. Thus, by indicating a laterdiscovery window 714 instead of earlier discovery windows 710 and 712, awireless station may not desire an FTM range determination untiloccurrence of the later discovery window 714. Accordingly, the wirelessstation may reduce power consumption by reducing the rate of FTMprocedures and corresponding FTM range determinations until occurrenceof the later discovery window 714. In such embodiments, a wirelessstation may continue to indicate every fourth discovery window tomaintain desired FTM range measurement rates and power consumption. Insuch an embodiment, although the rate of FTM range determinations may belower than those occurring in the pre-associations depicted in FIGS. 5and 6, such a configuration may be desirable with respect to thedistance between wireless stations, application responsiveness andaccuracy requirements, and other factors.

In some embodiments, a mobile wireless station (e.g., smartphone 102B)may switch between any number of NAN discovery window and FTMpre-associations. For example, a wireless station further than adistance threshold from a fixed wireless station (e.g., wireless station102D) may use the NAN discovery window and FTM communicationsassociation depicted in FIG. 7. Once the mobile wireless station is ator within the distance threshold from the fixed wireless station, themobile wireless station may switch to a higher rate of FTM rangemeasurements by associating FTM communications with more frequentdiscovery windows, such as by using to the NAN discovery window and FTMcommunications association depicted in FIG. 5. If the mobile wirelessstation moves away from the stationary station and is farther than thedistance threshold from the fixed wireless station, the mobile wirelessstation may switch to a NAN discovery window and FTM communicationsassociation having a lower rate of FTM range measurement determinations.

FIG. 8 depicts a process 800 for associating a NAN discovery window andan FTM procedure in accordance with the techniques described herein. Theprocess 800 may be performed by an initiating wireless station or aresponding wireless station. As shown in FIG. 8, discovery beacons fromanother wireless station in a NAN cluster may be detected (block 802). ANAN SDF may be sent during a first discovery window to trigger an FTMprocedure with the other wireless station (block 804). An FTMcommunication and an indication of a discovery window for the nextexpected FTM communication may then be sent or received (block 806).Next, another NAN SDF to initiate FTM communications is sent during theindicated discovery window (block 808). Another FTM communication and anindication of the discovery window for the next FTM communication issent or received (block 810). Additionally, as described above and asillustrated in FIG. 4, in some embodiments an FTM range report based ona previous FTM range measurement determination may be sent or received(block 812). The process 800 may continue to trigger FTM procedureswithin NAN discovery windows (block 814) until the process isterminated, such as when FTM range measurements are no longer obtained,a mobile wireless station moves out of a NAN cluster, a wireless stationis powered off, and so on.

FIG. 9 depicts a block diagram of an example embodiment of a wirelessstation 900, such as any of the wireless stations 102 of FIG. 1 orotherwise referred to herein. The mobile device 900 includes a processor902 and a non-transitory computer-readable medium (e.g., a memory 904)coupled to the processor. The memory 904 may include instructions 906executable by the processor 902.

The processor 902 may be further configured to or may execute theinstructions 906 to communicate according to a post discovery technique(e.g., a Wi-Fi direct technique) using credentials (e.g., a passphrase,encryption/decryption keys, or a combination thereof) obtained via apaging message (e.g., a paging request, a paging response, or acombination thereof). For example, in a particular embodiment, theprocessor 902 executes the instructions 906 perform one or moreoperations described in reference to the process 800 of FIG. 8, forexample.

The processor 902 may further be configured to or may execute theinstructions 906 to determine a post-discovery communication protocolfor communicating within a NAN cluster (e.g., NAN cluster 104) after adiscovery interval and to send, during the discovery interval, adiscovery message indicating the post-discovery communication techniquefor communicating within the cluster after the discovery interval.

The processor 902 may be configured to or may execute the instructions906 to receive, during a discovery interval, a discovery message from asecond wireless station (e.g., another of the wireless stations 102).The discovery message indicates a post-discovery communication protocolfor communicating within a NAN cluster (e.g., the NAN cluster 104) afterthe discovery interval. The processor 902 may be further configured toor may execute the instructions 906 to send a response to the secondwireless station using the post-discovery communication protocol.

The memory 904 may store additional instructions, data, or a combinationthereof. For example, the memory 904 may store an application 908. In aparticular illustrative embodiment, the application 908 may be a commonapplication shared or run by each device of a mobile device cluster,such as the NAN cluster 104. The application 908 may be a mobile devicesocial networking application, a mobile device gaming application, or acombination thereof. The memory 904 may store information related to thedynamic pre-association between NAN discovery windows and FTMcommunications described herein. For example, the memory 904 may storevarious configurations for different pre-associations between NANdiscovery windows and FTM communications that may enable switchingbetween configurations based a desired the responsiveness and powerconsumption, as described above. In some embodiments, the memory 904 maystore a default configuration defining a pre-association between NANdiscovery windows and FTM communications.

FIG. 9 also shows a display controller 910 that is coupled to theprocessor 902 and to a display 912. A coder/decoder (CODEC) 914 can alsobe coupled to the processor 902. A speaker 916 and a microphone 918 canbe coupled to the CODEC 914. FIG. 9 also indicates that a wirelesscontroller 920 can be coupled to the processor 902, to a radio frequency(RF) interface 922 (e.g., a transceiver), and to a wireless antenna 924.

In a particular embodiment, the processor 902, the display controller910, the memory 904, the CODEC 914, and the wireless controller 920 areincluded in a system-in-package or system-on-chip device 926. In aparticular embodiment, an input device 928 and a power supply 930 arecoupled to the system-on-chip device 926. Moreover, in a particularembodiment, as illustrated in FIG. 9, the display 912, the input device928, the speaker 916, the microphone 918, the RF interface 922, thewireless antenna 924, and the power supply 930 are external to thesystem-on-chip device 926. However, each of the display 912, the inputdevice 928, the speaker 916, the microphone 918, the RF interface 922,the wireless antenna 924, and the power supply 930 can be coupled to acomponent of the system-on-chip device 926, such as an interface or acontroller.

In addition, various illustrative logical blocks, configurations,modules, circuits, and algorithm steps described in connection with theembodiments disclosed herein may be implemented as electronic hardware,computer software, or combinations of both. Various illustrativecomponents, blocks, configurations, modules, circuits, and steps havebeen described above generally in terms of their functionality. Whethersuch functionality is implemented as hardware or software depends uponthe particular application and design constraints imposed on the overallsystem. Skilled artisans may implement the described functionality invarying ways for each particular application, but such implementationdecisions should not be interpreted as causing a departure from thescope of the present disclosure.

The steps of a process or algorithm described in connection with theembodiments disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module may reside in random access memory (RAM), flashmemory, read-only memory (ROM), programmable read-only memory (PROM),erasable programmable read-only memory (EPROM), electrically erasableprogrammable read-only memory (EEPROM), registers, hard disk, aremovable disk, a compact disc read-only memory (CD-ROM), or any otherform of storage medium known in the art. An exemplary non-transitory(e.g., tangible) storage medium is coupled to the processor such thatthe processor can read information from, and write information to, thestorage medium. In the alternative, the storage medium may be integralto the processor. The processor and the storage medium may reside in anapplication-specific integrated circuit (ASIC). The ASIC may reside in acomputing device or a user terminal. In the alternative, the processorand the storage medium may reside as discrete components in a computingdevice or user terminal.

The processor executable instructions may further be transmitted orreceived over a communications network using a transmission medium viathe network interface device/transceiver utilizing any one of a numberof transfer protocols (e.g., frame relay, internet protocol (IP),transmission control protocol (TCP), user datagram protocol (UDP),hypertext transfer protocol (HTTP), etc.). Example communicationsnetworks may include a local area network (LAN), a wide area network(WAN), a packet data network (e.g., the Internet), mobile telephonenetworks (e.g., cellular networks), Plain Old Telephone (POTS) networks,wireless data networks (e.g., Institute of Electrical and ElectronicsEngineers (IEEE) 802.11 family of standards known as Wi-Fi®, IEEE 802.16family of standards known as WiMax®), IEEE 802.15.4 family of standards,and peer-to-peer (P2P) networks, among others. In an example, thenetwork interface device/transceiver may include one or more physicaljacks (e.g., Ethernet, coaxial, or phone jacks) or one or more antennasto connect to the communications network. In an example, the networkinterface device/transceiver may include a plurality of antennas tocommunicate wirelessly using at least one of single-inputmultiple-output (SIMO), multiple-input multiple-output (MIMO), ormultiple-input single-output (MISO) techniques. The term “transmissionmedium” shall be taken to include any intangible medium that is capableof storing, encoding or carrying instructions for execution by themachine, and includes digital or analog communications signals or otherintangible media to facilitate communication of such software.

Further modifications and alternative embodiments of various aspects ofthe disclosure will be apparent to those skilled in the art in view ofthis description. Accordingly, this description is to be construed asillustrative only and is for the purpose of teaching those skilled inthe art the general manner of carrying out the disclosure. It is to beunderstood that the forms of the disclosure shown and described hereinare to be taken as examples of embodiments. Elements and materials maybe substituted for those illustrated and described herein, parts andprocesses may be reversed or omitted, and certain features of thedisclosure may be utilized independently, all as would be apparent toone skilled in the art after having the benefit of this description ofthe disclosure. Changes may be made in the elements described hereinwithout departing from the spirit and scope of the disclosure asdescribed in the following claims. Headings used herein are fororganizational purposes only and are not meant to be used to limit thescope of the description.

Further Embodiments

In a first example embodiment, there is disclosed a method forcommunication between two wireless devices including identifying, by afirst wireless device, a second wireless device in a Neighbor AwarenessNetworking (NAN) cluster available for a fine timing measurement (FTM)range determination and transmitting, by the first wireless device, aNAN service discovery frame (SDF) during a first NAN discovery window totrigger a first FTM communication with the second wireless device. Themethod also includes transmitting, by the first wireless device, anindication of a second NAN discovery window for an expected second FTMcommunication with the second wireless device.

In some embodiments, the NAN SDF may be transmitted on a first channeland the indication of the second NAN discovery window is transmitted ona second channel. In additional or alternative embodiments, the methodincludes transmitting, by the first wireless device, the first FTMcommunication to the second wireless device, and the NAN SDF may betransmitted on a first channel and the first FTM communication istransmitted on a second channel. In some embodiments, the methodincludes transmitting, by the first wireless device, a second FTMcommunication during the second NAN discovery window. In additional oralternative embodiments, the indication of the second NAN discoverywindow includes a time, a time interval, an indication of an SDF, or acombination thereof. In additional or alternative embodiments, firstwireless device includes a tablet computer or smartphone.

In a second example embodiment, there is disclosed a tangiblenon-transitory machine-readable medium storing computer-executableinstructions that, when executed by a processor, configure the processorto perform operations that include identifying, by a first wirelessdevice, a second wireless device in a Neighbor Awareness Networking(NAN) cluster available for a fine timing measurement (FTM) rangedetermination and transmitting, by the first wireless device, a servicediscovery frame (SDF) during a first NAN discovery window to trigger afirst FTM communication with second wireless device. The computerreadable medium includes further computer-executable instructions that,when executed by the at least one processor, configure the processor toperform operations that include transmitting, by the first wirelessdevice, an indication of a second NAN discovery window for an expectedsecond FTM communication with the second wireless device.

In some embodiments, the NAN SDF may be transmitted on a first channeland the indication of the second NAN discovery window is transmitted ona second channel. In additional or alternative embodiments, the computerreadable medium includes further computer-executable instructions that,when executed by the at least one processor, configure the processor toperform operations that include transmitting, by the first wirelessdevice, the first FTM communication to the second wireless device, andthe NAN SDF may be transmitted on a first channel and the first FTMcommunication is transmitted on a second channel. In some embodiments,the computer readable medium includes further computer-executableinstructions that, when executed by the at least one processor,configure the processor to perform operations that include transmitting,by the first wireless device, a second FTM communication during thesecond NAN discovery window. In additional or alternative embodiments,the indication of the second NAN discovery window includes a time, atime interval, an indication of an SDF, or a combination thereof.

In a third example embodiment, there is disclosed a wireless devicehaving a memory including computer instructions stored thereon and aprocessor configured to access the memory and executed the computerinstruction to perform operations that include identifying anotherwireless device in a Neighbor Awareness Networking (NAN) clusteravailable for a fine timing measurement (FTM) range determination andtransmitting a service discovery frame (SDF) during a first NANdiscovery window to trigger a first FTM communication with the otherwireless device. The processor is further configured to access thememory and execute the computer instructions to perform operations thatinclude transmitting, by the wireless device, an indication of a secondNAN discovery window for an expected second FTM communication with theother wireless device.

In some embodiments, the NAN SDF is transmitted on a first channel andthe indication of second NAN discovery window is transmitted on a secondchannel. In additional or alternative embodiments, the processor isfurther configured to access the memory and execute the computerinstructions to perform operations that include transmitting, by thefirst wireless device, the first FTM communication to the secondwireless device, and the NAN SDF is transmitted on a first channel andthe first FTM communication is transmitted on a second channel. Inadditional or alternative embodiments, the indication of a second NANdiscovery window comprises a time, a time interval, an indication of anSDF, or a combination thereof.

In a fourth example embodiment, there is disclosed a method forcommunication between two wireless devices that includes identifying, bya first wireless device, a second wireless device in a NeighborAwareness Networking (NAN) cluster available for a fine timingmeasurement (FTM) range determination and using, by the first wirelessdevice, a first pre-association between a first plurality of NANdiscovery windows and a respectively first plurality of FTMcommunications to obtain a first one or more FTM range measurements,wherein the first pre-association includes a first one or moreindications sent from the first wireless device and corresponding to oneor more of the first plurality of NAN discovery windows. The method alsoincludes using, by the first wireless device, a second pre-associationbetween a second plurality of NAN discovery windows and a respectivesecond plurality of FTM communications to obtain a second one or moreFTM range measurements, wherein the second pre-association includes asecond one or more indications sent from the first wireless device andcorresponding to one or more of the second plurality of NAN discoverywindows.

In some embodiments, the method includes transmitting, by the firstwireless device, one or more of the first plurality of FTMcommunications to the second wireless device. In additional oralternative embodiments, the first one or more indications comprise atime, a time interval, an indication of a service discovery frame (SDF),or a combination thereof. In additional or alterative embodiments, thesecond one or more indications comprise a time, a time interval, anindication of a service discovery frame (SDF), or a combination thereof.In additional or alternative embodiments, the first wireless devicecomprises a tablet computer or smartphone. In additional or alternativeembodiments, the first one or more indications and the first pluralityof FTM communications are transmitted on the same channel. In additionalor alternative embodiments, identifying, by a first wireless device, asecond wireless device in a Neighbor Awareness Networking (NAN) clusteravailable for a fine timing measurement (FTM) range determinationincludes detecting a beacon sent from the second wireless device.

In a fifth example embodiment, there is disclosed a tangiblenon-transitory machine-readable medium storing computer-executableinstructions that, when executed by a processor, configure the processorto perform operations that include identifying, by a first wirelessdevice, a second wireless device in a Neighbor Awareness Networking(NAN) cluster available for a fine timing measurement (FTM) rangedetermination and using, by the first wireless device, a firstpre-association between a first plurality of NAN discovery windows and arespectively first plurality of FTM communications to obtain a first oneor more FTM range measurements, wherein the first pre-associationincludes a first one or more indications sent from the first wirelessdevice and corresponding to one or more of the first plurality of NANdiscovery windows. The computer readable medium includes furthercomputer-executable instructions that, when executed by the at least oneprocessor, configure the processor to perform operations that includeusing, by the first wireless device, a second pre-association between asecond plurality of NAN discovery windows and a respective secondplurality of FTM communications to obtain a second one or more FTM rangemeasurements, wherein the second pre-association includes a second oneor more indications sent from the first wireless device andcorresponding to one or more of the second plurality of NAN discoverywindows.

In some embodiments, the computer readable medium further includescomputer-executable instructions that, when executed by the at least oneprocessor, configure the processor to perform operations that includetransmitting, by the first wireless device, one or more of the firstplurality of FTM communications to the second wireless device. Inadditional or alternative embodiments, the first one or more indicationscomprise a time, a time interval, an indication of a service discoveryframe (SDF), or a combination thereof. In additional or alterativeembodiments, the second one or more indications comprise a time, a timeinterval, an indication of a service discovery frame (SDF), or acombination thereof. In additional or alternative embodiments, the firstwireless device comprises a tablet computer or smartphone. In additionalor alternative embodiments, the first one or more indications and thefirst plurality of FTM communications are transmitted on the samechannel. In additional or alternative embodiments, identifying, by afirst wireless device, a second wireless device in a Neighbor AwarenessNetworking (NAN) cluster available for a fine timing measurement (FTM)range determination includes detecting a beacon sent from the secondwireless device.

In a sixth example embodiment, a wireless device is provided thatincludes means for identifying another wireless device in a NeighborAwareness Networking (NAN) cluster available for a fine timingmeasurement (FTM) range determination and means for transmitting aservice discovery frame (SDF) during a first NAN discovery window totrigger a first FTM communication with the other wireless device. Thewireless device further includes means for transmitting an indication ofa second NAN discovery window for an expected second FTM communicationwith the other wireless device.

In some embodiments, the NAN SDF is transmitted on a first channel andthe indication of second NAN discovery window is transmitted on a secondchannel. In additional or alternative embodiments, the wireless deviceincludes means for transmitting, by the first wireless device, the firstFTM communication to the second wireless device. In additional oralternative embodiments, the NAN SDF is transmitted on a first channeland the first FTM communication is transmitted on a second channel. Inadditional or alternative embodiments, the indication of a second NANdiscovery window comprises a time, a time interval, an indication of anSDF, or a combination thereof. In additional or alternative embodiments,the indication of a second NAN discovery window comprises a time, a timeinterval, an indication of an SDF, or a combination thereof. Inadditional or alternative embodiments, the wireless device includes atransceiver coupled to the processor and is configured to transmit theSDF over at least one radio frequency (RF). In additional or alternativeembodiments, the wireless device includes an antenna coupled to thetransceiver. In additional or alternative embodiments, the wirelessdevice includes a display coupled to the processor.

In a seventh example embodiment, there is disclosed a wireless devicethat includes means for identifying, from a first wireless device, asecond wireless device in a Neighbor Awareness Networking (NAN) clusteravailable for a fine timing measurement (FTM) range determination andmeans for using a first pre-association between a first plurality of NANdiscovery windows and a respectively first plurality of FTMcommunications to obtain a first one or more FTM range measurements,wherein the first pre-association includes a first one or moreindications sent from the first wireless device and corresponding to oneor more of the first plurality of NAN discovery windows. The wirelessdevice also includes means for using a second pre-association between asecond plurality of NAN discovery windows and a respective secondplurality of FTM communications to obtain a second one or more FTM rangemeasurements, wherein the second pre-association includes a second oneor more indications sent from the first wireless device andcorresponding to one or more of the second plurality of NAN discoverywindows.

The invention claimed is:
 1. A neighbor awareness networking (NAN)device for performing a fine timing measurement (FTM) with a peerdevice, the NAN device comprising memory and processing circuitryconfigured to: cause to send a NAN service discovery frame to the peerdevice, the NAN service discovery frame comprising an indication of afirst window associated with the NAN device; cause to send an FTMrequest to the peer device during the first window; receive, from thepeer device, an FTM response, wherein at least one of the FTM request orthe FTM response comprises an indication of a second window; receive,from the peer device, during the second window, an FTM frame; and causeto send an FTM range report to the peer device, the FTM range reportcomprising an indication of a range based on the FTM frame.
 2. Thedevice of claim 1, wherein the FTM request is a first FTM request, andwherein the memory and processing circuitry are further configured tocause to send, to the peer device, during the second window, a secondFTM request.
 3. The device of claim 1, wherein the FTM request is afirst FTM request, and wherein the memory and processing circuitry arefurther configured to receive, from the peer device, during the secondwindow, a second FTM request.
 4. The device of claim 1, wherein the FTMrequest indicates a request for a single burst session.
 5. The device ofclaim 1, wherein the memory and processing circuitry are furtherconfigured to determine the range, wherein the range indicates adistance between the NAN device and the peer device.
 6. The device ofclaim 1, wherein the NAN service discovery frame comprises an indicationof a channel.
 7. The device of claim 1, further comprising a transceiverconfigured to transmit and receive wireless signals.
 8. The device ofclaim 7, further comprising one or more antennas coupled to thetransceiver.
 9. A non-transitory computer-readable medium storingcomputer-executable instructions which when executed by one or moreprocessors result in performing operations comprising: receiving, at afirst device from a second device, a neighbor awareness networking (NAN)service discovery frame comprising an indication of a first windowassociated with the second device; receiving, at the first device fromthe second device, a fine timing measurement (FTM) request during thefirst window; causing to send, to the second device, an FTM response,wherein at least one of the FTM request or the FTM response comprises anindication of a second window; and causing to send, to the second deviceduring the second window, an FTM frame.
 10. The non-transitorycomputer-readable medium of claim 9, wherein the FTM request is a firstFTM request, and wherein the operations further comprise causing tosend, to the second device during the second window, a second FTMrequest.
 11. The non-transitory computer-readable medium of claim 9,wherein the FTM request is a first FTM request, and wherein theoperations further comprise receiving, from the second device during thesecond window, a second FTM request.
 12. The non-transitorycomputer-readable medium of claim 9, wherein the FTM request indicates arequest for a single burst session.
 13. The non-transitorycomputer-readable medium of claim 9, wherein the operations furthercomprise receiving, from the second device, an FTM range reportcomprising an indication of a range determination based on the FTMframe.
 14. The non-transitory computer-readable medium of claim 9,wherein the NAN service discovery frame comprises an indication of achannel.
 15. A method for performing a fine timing measurement (FTM)with a peer device, the method comprising: causing to send, by one ormore processors of a neighbor awareness networking (NAN) device, to thepeer device, a NAN service discovery frame comprising an indication of afirst window associated with the NAN device; causing to send, by the oneor more processors, to the peer device, an FTM request to the peerdevice during the first window; receiving, by the one or moreprocessors, from the peer device, an FTM response, wherein at least oneof the FTM request or the FTM response comprises an indication of asecond window; receiving, by the one or more processors, from the peerdevice during the second window, an FTM frame; and causing to send, bythe one or more processors, an FTM range report to the peer device, theFTM range report comprising an indication of a range based on the FTMframe.
 16. The method of claim 15, wherein the FTM request is a firstFTM request, the method further comprising causing to send, to the peerdevice during the second window, a second FTM request.
 17. The method ofclaim 15, wherein the FTM request is a first FTM request, the methodfurther comprising receiving, from the peer device during the secondwindow, a second FTM request.
 18. The method of claim 15, wherein theFTM request indicates a request for a single burst session.
 19. Themethod of claim 15, further comprising determining the range, whereinthe range indicates a distance between the NAN device and the peerdevice.
 20. The method of claim 15, wherein the NAN service discoveryframe comprises an indication of a channel.